Daylength for broiler breeders - have we got it right?

摘要

Research suggests that the right lighting pattern for egg-laying hens will not necessarily get the best results from breeders. From the start of the broiler industry in the 1950s, recommendations for lighting breeders have invariably been based on programmes designed for lighting egg-laying hybrids. Typically, these involve an initial period of long days followed by a step-down programme to reach 8 hours by 1-2 weeks of age. The birds are held on 8 hours until about 20 weeks and then transferred to a 10-, 11- or 12-hour day to initiate egg production, followed by a series of weekly increments to reach a maximum of 15 or 16 hours.